The present invention relates to machining and registering methods well suited for use with torque-transmitting tools such as out-of-round drive studs.
U.S. Pat. No. 5,644,958, assigned to the assignee-of the present invention, discloses a quick release mechanism for an extension bar suitable for use with a socket wrench. This quick release mechanism utilizes a diagonally-oriented, stepped bore formed in the drive stud of the extension bar.
The machining of such diagonal bores presents manufacturing difficulties. In particular, there is a need to register the drive stud reliably with respect to the drilling axis. Poor registration can result in misplaced machined surfaces, and is therefore to be avoided. Proper location of a diagonal bore is even more difficult, because the oblique orientation of such a bore can cause the bore to deviate from the desired drilling axis, either at the start of the bore or during the drilling operation. Furthermore, when a drill is passed completely through the drive stud on a diagonal axis, there is a tendency for the drill to break as it exits the drill stud. This tendency is especially great for a stepped bore, which requires a relatively smaller diameter portion at the front of the drill.